Dear Timur Tabi,
In message AANLkTilrFhTwnQgQX9NVmplaBl8HpISZY97HKK73-ncz@mail.gmail.com you wrote:
On Thu, May 27, 2010 at 1:11 PM, Wolfgang Denk wd@denx.de wrote:
get_ram_size() used to use "long" data types for addresses and data, which in limited it to systems with less than 4 GiB memory. As more and more systems are coming up with bigger memory resources, we adapt the code to use phys_addr_t / phys_size_t data types instead.
Signed-off-by: Wolfgang Denk wd@denx.de Cc: Timur Tabi timur@freescale.com
The problem is that on all of our PowerPC boards, the TLBs only map the lower 2GB of memory, regardless as to how much is present. So we still can't use get_ram_size() to determine how much memory is in the system, because any attempt to access memory higher than 2GB will fail.
Now this is your problem, then, and you should kno how to fix it.
And even if we did have TLBs for all of memory, an attempt to access RAM that doesn't exist will cause a machine check, which will hang U-Boot. So we still couldn't use get_ram_size() to determine how much RAM actually exists.
Please see how it's done on all other PowerPC systems, and do similar.
-long get_ram_size(volatile long *base, long maxsize) +phys_size_t get_ram_size(volatile phys_addr_t *base, phys_size_t maxsize)
I don't think you want 'base' to be a pointer to phys_addr_t, because the pointer type determines how much is read/written in a single operation. I don't think you want to be doing 64-bit reads and writes.
I don't know your mnemory bus. This is an RFC patch.
Plus, you still have this:
for (cnt = (maxsize / sizeof (long)) >> 1; cnt > 0; cnt >>= 1) { addr = base + cnt; /* pointer arith! */ sync (); save[i++] = *addr; sync (); *addr = ~cnt; }
I'm not quite sure what this loop is doing, but I have a suspicion the "sizeof(long)" does not match with "phys_addr_t *base".
Right. This needs to be fixed.
Thanks for pointing out.
Best regards,
Wolfgang Denk